I've encountered these issues many times in the past while deploying custom MDBs and I've deduced the following rules of thumb hoping they can be useful:

1. Never change the prbeans.jars.
   Always add a new jar module with only the deployment descriptors of your custom MDB.
   In this way you do not risk to accidentally break what is working OOTB
    
2. When you apply a change and it doesn't work always return to the OOTB EAR before applying the next change. 
   In this way you do not risk to forget the list of changes applied.

Now returning to the reported issue it looks like you have replaced the default MDB resource adapter (hornetq-ra) with the MQ  resource adapter (wmq.jmsra.rar).

This is not correct as hornetq-ra is still required by the Pega OOTB PRAsync MDB for agent processing.

The following exception prove it: 

JBAS014612: Operation ("deploy") failed - address: ([("deployment" => "prpc_j2ee14_jboss61JBM.ear")]) - failure description: {"JBAS014671: Failed services" => {
    "jboss.deployment.subunit.\"prpc_j2ee14_jboss61JBM.ear\".\"prbeans.jar\".component.PRAsync.START" => "org.jboss.msc.service.StartException in service jboss.deployment.subunit.\"prpc_j2ee14_jboss61JBM.ear\".\"prbeans.jar\".component.PRAsync.START: java.lang.RuntimeException: com.ibm.mq.connector.DetailedResourceAdapterInternalException: MQJCA1011: Failed to allocate a JMS connection., error code: MQJCA1011 An internal error caused an attempt to allocate a connection to fail. See the linked exception for details of the failure.
    Caused by: java.lang.RuntimeException: com.ibm.mq.connector.DetailedResourceAdapterInternalException: MQJCA1011: Failed to allocate a JMS connection., error code: MQJCA1011
...
Caused by: com.ibm.mq.MQException: JMSCMQ0001: WebSphere MQ call failed with compcode '2' ('MQCC_FAILED') reason '2538' ('MQRC_HOST_NOT_AVAILABLE').
    Caused by: com.ibm.mq.jmqi.JmqiException: CC=2;RC=2538;AMQ9204: Connection to host 'localhost(1414)' rejected. [1=com.ibm.mq.jmqi.JmqiException[CC=2;RC=2538;AMQ9213: A communications error for 'TCP' occurred. [1=java.net.ConnectException[Connection refused: connect],3=connnectUsingLocalAddress,4=TCP,5=Socket.connect]],3=localhost(1414),5=RemoteTCPConnection.connnectUsingLocalAddress]
    Caused by: com.ibm.mq.jmqi.JmqiException: CC=2;RC=2538;AMQ9213: A communications error for 'TCP' occurred. [1=java.net.ConnectException[Connection refused: connect],3=connnectUsingLocalAddress,4=TCP,5=Socket.connect]
    Caused by: java.net.ConnectException: Connection refused: connect"

If so please revert the standalone-full.xml to use the default resource adapter:

<subsystem xmlns="urn:jboss:domain:ejb3:1.5">
   <session-bean>
      ...
   </session-bean>
   <mdb>
      <resource-adapter-ref resource-adapter-name="${ejb.resource-adapter-name:hornetq-ra}"/>
      <bean-instance-pool-ref pool-name="mdb-strict-max-pool"/>
   </mdb>
   ...
</subsystem>

For further details please see the following link:
https://collaborate.pega.com/question/issues-connecting-websphere-mq-pega-using-mdb-listener

Then redeploy the OOTB EAR file prpc_j2ee14_jboss61JBM.ear and ensure that Pega runs correctly (agents are started and no exceptions are reported in the logs) and JBOSS - MQ integration is successful

Once you are sure of the above create a custom jar module for your new MDB with the following content in the META-INF directory:

Please note that:

• in META-INF\ejb-jar.xml activation-config-property entries are defined to provide the MQ configuration details:
  
• in META-INF\jboss-ejb3.xml the custom MDB is bound to the MQ resource-adapter:
  

The sample module is attached for your reference.

Then add the newly created module to the original prpc_j2ee14_jboss61JBM.ear EAR file by applying the following steps:
 

1. Unzip original Pega EAR prpc_j2ee14_ws.ear
2. Add the custom jar module. This jar is meant to be included into the original Pega 7 ear at the same level of the existing prbeans.jar as you may see below:
   
3. Edit the application.xml inside the META-INF directory and add the new module as highlighted below:
   
4. Edit the jboss-deployment-structure.xml inside the META-INF directory and add the new module as highlighted below:
   
5. Notice that in the CustomMDB.jar/META-INF/ejb-jar.xml there are activation-config-property-value values with ${...} 
   Those are the system properties providing MQ Resource adapter configuration which you should define in the standalone-full.xml as described in the following SA post:
   https://stackoverflow.com/questions/14586657/system-properties-in-standalone-full-xml
6. In the same JBoss configuration file enable property substitution in deployment descriptors:

   <subsystem xmlns="urn:jboss:domain:ee:1.2">
       <global-modules>
          <module name="com.oracle"/>
          <module name="org.jboss.remoting-jmx" slot="main"/>
        </global-modules>
        <spec-descriptor-property-replacement>true</spec-descriptor-property-replacement>
        <jboss-descriptor-property-replacement>true</jboss-descriptor-property-replacement>
        <annotation-property-replacement>false</annotation-property-replacement>
   </subsystem>

   For further details please see the following Community post:
   https://collaborate.pega.com/question/error-while-configuring-listener-eap-64

Hope it helps!